Kuretake ZIG Cocoiro Body Letter Pen, Beni-Suika (LPC-13S)

I’ve bought the set (pen with 2 refills) twice now but both times 2 of the 3 cartridges are dried up. Is there a trick to rehydrate them?

Please tell me the refill ink is not watercolor...but only if true. :)

I'm buying several of the "inner pens"...can I use one body and just switch them out as needed, or do I need a separate body for each?

It this pen designed so that the end of the refill sticks out the bottom when the pen is capped? it looks like a piece is missing.